Results 1 - 10 of 4274
Results 1 - 10 of 4274. Search took: 0.026 seconds
|Sort by: date | relevance|
[en] Whole body bone scan has been used to confirm bone metastasis and follow-up study with radio isotope. However, if the factors related to 99mTc uptake and waiting time for study are inappropriate, it would be image of low quality. The purpose of present study was to investigate correlation between the evaluation index of renal function and uptake of radiopharmaceuticals. The population for this retrospective study consisted of 387 patients who underwent whole body bone scan between June 2012 and December 2012. As a result of quantitative and qualitative analysis, we were able to confirm that GFR of less than normal range and creatinine levels in blood of more than average are more likely to be under the mean uptake rate. As a result of analysis on the indicator affecting soft-tissue and bone uptake, the correlation of all elements was somewhat low. Also there are no statistically significances due to the other parameters we did not deal with. Therefore, further research on additional factors is needed for exact study and improvement of the image quality
[en] To compare the accuracy of artificial neural network (ANN) analysis and multivariate regression analysis (MVRA) for renal stone fragmentation by extracorporeal shock wave lithotripsy (ESWL). A total of 276 patients with renal calculus were treated by ESWL during December 2001 to December 2006. Of them, the data of 196 patients were used for training the ANN. The predictability of trained ANN was tested on 80 subsequent patients. The input data include age of patient, stone size, stone burden, number of sittings and urinary pH. The output values (predicted values) were number of shocks and shock power. Of these 80 patients, the input was analyzed and output was also calculated by MVRA. The output values (predicted values) from both the methods were compared and the results were drawn. The predicted and observed values of shock power and number of shocks were compared using 1:1 slope line. The results were calculated as coefficient of correlation (COC) (r2 ). For prediction of power, the MVRA COC was 0.0195 and ANN COC was 0.8343. For prediction of number of shocks, the MVRA COC was 0.5726 and ANN COC was 0.9329. In conclusion, ANN gives better COC than MVRA, hence could be a better tool to analyze the optimum renal stone fragmentation by ESWL (Author).
[en] To systematically determine the treatment outcomes of percutaneous microwave ablation (MWA) in patients with malignant renal tumor. Original studies that reported the clinical outcomes of MWA in patients with malignant renal tumors were identified in MEDLINE and EMBASE from 2012 to June 30, 2017. Inverse variance and random-effects models were used to evaluate and acquire meta-analytic summary estimates of various clinical outcomes, including technical outcomes (technical success rate [TSR] and technical efficacy rate [TER]), oncologic outcomes (local tumor recurrence rate [LRR], cancer-specific survival rate [CSSR], and overall survival rate [OSR]), and complications. Among the 145 articles screened, 13 articles including 567 patients carrying 616 malignant renal tumors were included in the meta-analysis. The meta-analytic pooled TSR and TER were 97.3% (95% confidence interval, 94.3–99.4%; I2 = 0.0%) and 97.6% (95.0–99.4%, I2 = 48.5%), respectively. The meta-analytic pooled LRR was 2.1% (0.3–4.7%, I2 = 54.1%). At 1-, 2-, 3-, and 5-year follow-up time points, the meta-analytic pooled CSSRs were 99.1% (97.2–100.0%; I2 = 0.0%), 98.4% (95.1–100.0%; I2 = 31.2%), 97.6% (93.4–99.9%; I2 = 52.3%), and 96.9% (93.3–99.2%; I2 = 0.0%) respectively, while the OSRs were 98.3% (96.1–99.8%; I2 = 0.0%), 94.9% (91.7–97.5%; I2 = 0.0%), 86.8% (81.9–91.1%; I2 = 22.1%), and 81.9% (75.4–87.6%; I2 = 0.0%). In terms of major complications, a 1.8% (0.6–3.3%; I2 = 0.0%) rate of meta-analytic pooled incidence was found. Microwave ablation showed favorable technical and oncologic outcomes with a low incidence of major complications. Hence, image-guided percutaneous MWA can be considered as a safe and effective treatment for malignant renal tumors
[en] In an attempt to evaluate the various serum hormonal changes in terminal renal failure, the fasting T4, T3, rT-3, gastrin, secretin prolactin, and aldosterone were measured by radioimmunoassay in 12 patients with chronic renal failure, who were admitted Chosun University Hospital from January to June, 1981. From the analysis the following results were obtained. 1. Mean values of serum hormonal concentration in 10 normal control were as follows: T4, 12.93±2.00 ug/ml; T3, 113.0±28.7 ng/ml; rT3, 0.11±0.10 ng/ml; gastrin, 100.0±47.1 pg/ml; secretin, 32.46±11.45 pg/ml; prolactin, 11.0±3.6 ng/ml; aldosterone 137.0±58.5 pg/ml. 2. Mean values of serum hormonal concentration in 12 chronic renal failure were as follows; T4, 7.34±2.43 ug/ml; T3, 71.0±19.1 ng/ml; reverse T3, 0.38±0.19 ng/ml; gastrin, 162.5±40.2 pg/ml; secretin, 107.50±20.48 pg/ml; prolactin, 34.0±17.2 ng/ml; aldosterone, 86.5±19.8 pg/ml. 3. In chronic renal failure group, serum T4, T3, and adosterone level were significantly lower than those of the control group, but serum rT-3, gastrin, secretin and prolactin were significantly higher than those of the control group. 4. In the view of the correlation between serum hormonal concentrations and serum creatine levels in patients with chronic renal failure, rT3, gastrin, secretin and prolactin showed increasing tendency (positive correlations), whereas T4, T3 and aldosterone showed decreasing tendency (negative correlations) with increment of serum creatinine levels. And so, we observed the negative correlation between T3 and rT3.
[en] During a four year period, ending May 1987, 154 cases of symptomatic staghorn calculi have been treated by percutaneous nephrolithotomy. Of these patients,86% were discharged completely stone free with the remainder having fragments less than 5 mm in greatest diameter. More than one operative procedure during the same hospitalizations was required in 24% of patients and multiple percutaneous tracts were established in excess of 73% of them. Significant complications occurred in 16% of patients and there was one death. Most complications can be generally by minimized by careful approach and manageable by interventional radiological means. The management of patients with staghorn calculi requires a comprehensive understanding of the renal anatomy, selection of appropriate percutaneous nephrostomy tract sites, and radiologic-urologic expertise needed to remove the large stone mass. The advent of extracorporeal shock wave lithotripsy will not abolish the need for nephrolithotomy, particularly complex stones such as staghorn calculi
[en] To retrospectively evaluate the intermediate results of radiofrequency ablation (RFA) of small renal masses (SRMs). Percutaneous or laparoscopic RFA was performed on 48 renal tumors in 47 patients. The follow-up studies included a physical examination, chest radiography, creatinine level, and contrast-enhanced CT or MRI. To confirm the pathologic criteria of complete ablation, 35 patients underwent a follow-up biopsy. Recurrence was defined as contrast enhancement on imaging studies after 3 months, lesion growth at subsequent imaging, or viable cancer cells on follow-up biopsy. Technical success was achieved in 43 (89.6%) of 48 renal tumors. The mean tumor size was 2.3 cm and the mean follow-up period was 49.6 months. Repeated RFA was necessary in 5 tumors due to incomplete ablation. The overall complication rate was 35.8%, of which 96.2% were mild complications. Serum creatinine levels at 12 months after RFA did not differ from those before RFA (1.28 vs. 1.36 mg/dL). Four patients were found to have recurrence at various follow-up intervals, and distant metastasis was not found in any cases. RFA appears to be a useful treatment for selected patients with SRMs. Our 4-year follow-up results disclose an excellent therapeutic outcome with RFA, while achieving effective local tumor control.
[en] We evaluated the effectiveness and clinical usefulness of percutaneous renal biopsy by using automated biopsy gun under the real-time ultrasonographic guidance that was performed in 17 patients with diffuse renal disease. We retrospectively analysed the histopathological diagnosis and the patients' status after percutaneous renal biopsy.Adequate amount of tissue for the histologic diagnosis could be obtained in al patients. Histopathologic diagnosis included the minimal change nephrotic syndrome in 6 patients, the membrano proliferative glomerulonephritis in 4,the membranous glomerulonephritis in 2, the glomerulosclerosis in 2, Ig A nephropathy in 2, and the normal finding in 1. Significant complication occurred in only one patient who developed a transient loss of sensation at and around the biopsy site. In conclusion, automated biopsy gun was a very useful device in performing percutaneous biopsy for diffuse renal disease with a high success rate and a low complication rate
[en] To assess the feasibility of susceptibility-weighted imaging (SWI) while monitoring changes in renal oxygenation level after water loading. Thirty-two volunteers (age, 28.0 ± 2.2 years) were enrolled in this study. SWI and multi-echo gradient echo sequence-based T2* mapping were used to cover the kidney before and after water loading. Cortical and medullary parameters were measured using small regions of interest, and their relative changes due to water loading were calculated based on baseline and post-water loading data. An intraclass correlation coefficient analysis was used to assess inter-observer reliability of each parameter. A receiver operating characteristic curve analysis was conducted to compare the performance of the two methods for detecting renal oxygenation changes due to water loading. Both medullary phase and medullary T2* values increased after water loading (p < 0.001), although poor correlations were found between the phase changes and the T2* changes (p > 0.05). Interobserver reliability was excellent for the T2* values, good for SWI cortical phase values, and moderate for the SWI medullary phase values. The area under receiver operating characteristic curve of the SWI medullary phase values was 0.85 and was not different from the medullary T2* value (0.84). Susceptibility-weighted imaging enabled monitoring changes in the oxygenation level in the medulla after water loading, and may allow comparable feasibility to detect renal oxygenation level changes due to water loading compared with that of T2* mapping
[en] Purpose: Respiratory motion is a source of artifacts that reduce image quality in PET. Four dimensional (4D) PET/CT is one approach to overcome this problem. Existing techniques to limiting the effects of respiratory motions are based on prospective phase binning which requires a long acquisition duration (15–25 min). This time is uncomfortable for the patients and limits the clinical exploitation of 4D PET/CT. In this work, the authors evaluated an existing method and an alternative retrospective binning method to reduce the acquisition duration of 4D PET/CT. Methods: The authors studied an existing mixed-amplitude binning (MAB) method and an alternative binning method by mixed-phases (MPhB). Before implementing MPhB, they analyzed the regularity of the breathing patterns in patients. They studied the breathing signal drift and missing CT slices that could be challenging for implementing MAB. They compared the performance of MAB and MPhB with current binning methods to measure the maximum uptake, internal volume, and maximal range of tumor motion. Results: MPhB can be implemented depending on an optimal phase (in average, the exhalation peak phase −4.1% of the entire breathing cycle duration). Signal drift of patients was in average 35% relative to the breathing amplitude. Even after correcting this drift, MAB was feasible in 4D CT for only 64% of patients. No significant differences appeared between the different binning methods to measure the maximum uptake, internal volume, and maximal range of tumor motion. The authors also determined the inaccuracies of MAB and MPhB to measure the maximum amplitude of tumor motion with three bins (less than 3 mm for movement inferior to 12 mm, up to 6.4 mm for a 21 mm movement). Conclusions: The authors proposed an alternative binning method by mixed-phase binning that halves the acquisition duration of 4D PET/CT. Mixed-amplitude binning was challenging because of signal drift and missing CT slices. They showed that more than three bins were necessary for a more accurate measurement of the maximum amplitude of the tumor motion. However, the current 4D-CT technology limits the increase of the number of bins in 4D PET/CT because of missing CT slices. One can reconstruct 4D PET images with more bins but without attenuation/scatter correction
[en] We undertook a combined retrospective and prospective analysis of duplex Doppler examinations performed over a perion of 10 months in order to assess the value of Doppler study(DS)in evaluating renal allograft dysfunction. A total of 110 DS on 82 transplant patients were performed including 79 normal transplants, 29 acute rejections and 2 acute tubular necrosis(ATN). Resistive Index(RI) in 79 normal transplants ranged from 0.44 to 0.7 (Mean;0.59+0.07) in the arcuate artery, and from 0.45 to 0.75(mean;0.61+0.08) in the interlobar artery. RI in 29 cases of acute rejection ranged from 0.61 to 1.0(mean ;0.77+0.10)in the interlobar artery. In ATNRI ranged from 0.59 to 0.63(mean 0.62) in the arcuate artery, and from 0.59 to 0.62(mean 0.61) in the interlobar artery. The RI in acute rejection is significantly higher than that of the normal transplants (p<0.001). With a resistive index greater than 0.8, 100% positive predictive value was obtained for the diagnosis of acute rejection. The value less than 0.7 was unlikely to suggest acute rejection(negative predictive value 92%)